At the very top, that's a D-Link router.
Below that is a... looks like 16 port switch with two empty link ports.
Below that is a series of Sun appliance servers, not sure why they're using one as a firewall, guess they like software versions better than hardware.
All the way at the bottom is another 16 port switch, not sure why they couldn't just upgrade to a 40 port, guess they use the top one for server traffic and the bottom for local traffic.
The last thing is a fiber optic switch, probably being used for high speed uplinks between departments. However, only one port is actually being used, which is rather peculiar...